Vehicles, such as passenger vehicles, include a front bulkhead provided in a front part of a vehicle body. A bumper is arranged in front of the front bulkhead. One of such vehicle body front part structure is disclosed, for example, in Patent Document 1.
The vehicle body front part structure disclosed in Patent Document 1 includes left and right front side frames located in the front part of the vehicle body and extending in a longitudinal direction of the vehicle body, and a front bulkhead mounted between front ends of the left and right front side frames. The front bulkhead is a frame-like component having a substantially rectangular shape in a front view, and includes a bulkhead lower member extending in a vehicle width direction, left and right bulkhead side members extending upward from opposite ends of the bulkhead lower member, and a bulkhead upper member extending between upper ends of the left and right bulkhead side members.
The left and right bulkhead side members are each formed to have a substantially U-shaped cross section, in a plan view, opened outward in the vehicle width direction. More specifically, the left and right bulkhead side members have, respectively, left and right front walls facing toward the front of the vehicle body, left and right rear walls located rearwardly of the left and right front walls at a distance therefrom, and left and right inner walls connecting the left and right front walls and the left and right rear walls.
However, since the left and right bulkhead side members have such a cross-sectional shape opened outward in the vehicle width direction as described above, there is a limit to the extent to which the rigidity of the left and right bulkhead side members can be increased. In order to reduce vibration of the vehicle body during traveling of the vehicle, it is necessary to increase the rigidities of the front bulkhead and its peripheral parts in the vehicle body front part. If the left and right bulkhead side members are each formed to have a closed cross section to increase the rigidity of the front bulkhead, the weight of the vehicle body would be increased. Thus, there is a room for further improvement in this respect.